Regarding an antenna of a wireless communication apparatus or the like that receives radio waves from another wireless communication apparatus, when the communication apparatus receives radio waves from a radio wave generation source such as an opposite station, it is necessary to adjust the direction of the antenna in order to maximize the reception quality. For example, to adjust the direction of the antenna, an operator first visually makes a coarse adjustment by hand so that the front face of the antenna points to the radio wave generation source. Then, a fine adjustment of the antenna direction is made by hand to the angle at which the maximum reception level output is obtained by using a reception level monitor such as a voltmeter. However, in the case of adjusting the direction of an antenna by hand as described above, an installation error is likely to occur, and it takes a long time to adjust the antenna in the most appropriate direction.
In relation to the above technique, Patent Literature 1 discloses a wireless communication apparatus that is easy to maintain. The wireless communication apparatus disclosed in Patent Literature 1 includes wireless transmitting and receiving means using a directional antenna, and image pickup means having an optical axis which coincides with a radio-wave direction of the directional antenna for photographing an image of the radio-wave direction at a predetermined timing. Further, the wireless communication apparatus disclosed in Patent Literature 1 compares reference image data and image-pickup image data which are photographed by the image pickup means. From a result of the comparison, it detects and notifies that an object is toward a direction to block radio waves.
Further, Patent Literature 2 discloses an antenna apparatus including a directional angle visualizing device capable of coinciding a directivity of an antenna with an opposite antenna and avoiding the influence of obstacles present within a directional angle of the antenna. The wireless communication apparatus disclosed in Patent Literature 2 includes a cylindrical-shaped directional angle visualizing device which has a diameter and a length in which a view in a range of a predetermined directional angle, when seen from the side of one end of the device, can be seen on the side of the other end of the device, the cylindrical-shaped directional angle visualizing device being mounted on an antenna body parallel to the directivity thereof, and a mounting device capable of adjusting the directivity of the antenna body and fixing the antenna body toward any direction. Further, the predetermined directional angle of the directional angle visualizing device disclosed in Patent Literature 2 is a power half width of the antenna body, and the directional angle visualizing device is provided with scale means on the side of the other end of the device.